/*
 * ProGuard -- shrinking, optimization, obfuscation, and preverification of Java bytecode.
 *
 * Copyright (c) 2002-2018 GuardSquare NV
 *
 * This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public
 * License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later
 * version.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied
 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along with this program; if not, write to the Free
 * Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */
package proguard.optimize.evaluation;

import proguard.classfile.Clazz;
import proguard.classfile.attribute.CodeAttribute;
import proguard.evaluation.BasicBranchUnit;
import proguard.evaluation.value.Value;

/**
 * This BranchUnit remembers the branch unit commands that are invoked on it.
 *
 * @author Eric Lafortune
 */
class TracedBranchUnit extends BasicBranchUnit {
    private boolean isFixed;

    // Implementations for BasicBranchUnit.

    public void reset() {
        super.reset();

        isFixed = false;
    }

    // Implementations for BranchUnit.

    public void branch(Clazz clazz, CodeAttribute codeAttribute, int offset, int branchTarget) {
        super.branch(clazz, codeAttribute, offset, branchTarget);

        isFixed = true;
    }

    public void branchConditionally(Clazz clazz, CodeAttribute codeAttribute, int offset, int branchTarget,
        int conditional) {
        if (conditional == Value.ALWAYS) {
            // Always branch.
            super.branch(clazz, codeAttribute, offset, branchTarget);

            isFixed = true;
        } else if (conditional == Value.MAYBE) {
            if (!isFixed) {
                // Maybe branch.
                super.branchConditionally(clazz, codeAttribute, offset, branchTarget, conditional);
            }
        } else {
            super.wasCalled = true;
        }
    }
}
